Mozart: Directly associate the renderer with the view tree.

mojo/services/ui/views/interfaces/view_trees.mojom

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 [DartPackage="mojo_services"]
 module mojo.ui;
 
 import "mojo/public/interfaces/application/service_provider.mojom";
+import "mojo/services/gfx/composition/interfaces/renderers.mojom";
 import "mojo/services/ui/views/interfaces/layouts.mojom";
 import "mojo/services/ui/views/interfaces/views.mojom";
 
 // A view tree token is an opaque transferable reference to a view tree.
 //
 // The ViewManager provides each view tree with a unique view tree token when
 // it is registered.  The token can subsequently be passed to other
 // applications and used as a way to refer to the tree.
 //
 // View tree tokens should be kept secret and should only be shared with
@@ skipping 47 matching lines @@
   GetToken() => (ViewTreeToken token);
 
   // Gets a service provider to access services which are associated with
   // the view tree such as input, accessibility and editing capabilities.
   // The view tree service provider is private to the view tree and should
   // not be shared with anyone else.
   //
   // See |mojo.ui.InputDispatcher|.
   GetServiceProvider(mojo.ServiceProvider& service_provider);
 
+  // Sets where the view tree's scene graph will be rendered.
+  //
+  // If |renderer| is null, disconnects the view tree from the renderer
+  // causing its previous renderer to be destroyed.
+  //
+  // See also: |mojo.gfx.composition.Compositor.CreateRenderer()|.
+  SetRenderer(mojo.gfx.composition.Renderer? renderer);
+
   // Requests that the view tree's OnLayout() method be called to compute a
   // new layout due to a change in the view tree's layout information.
   RequestLayout();
 
   // Sets the root of the view tree and assigns it the provided |root_key|
   // to distinguish it from any other roots this view tree has had.
   //
   // It is a good idea to provide a distinct |root_key| each time a new root
   // is set so that callbacks related to the root can be clearly distinguished
   // across these changes.
@@ skipping 60 matching lines @@
 
   // Called when the root view has become unavailable.
   //
   // The root may become unavailable for many reasons such being unregistered
   // by its application, abnormal termination of its application, or
   // being reparented into a different view tree.
   //
   // The implementation should invoke the callback once the event has
   // been handled.
   OnRootUnavailable(uint32 root_key) => ();
+
+  // Called when the tree's renderer connection closed unexpectedly.
+  //
+  // The implementation should invoke the callback once the event has
+  // been handled.
+  OnRendererDied() => ();
 };